面向高铁信号系统工程测试的测试建模方法

Testing Modeling Method for Engineering Testing of High-Speed Railway Signaling System

高铁信号系统工程测试关注系统中各设备间的复杂行为关系和状态同步,工程测试的测试建模方法缺少复杂行为交互和同步机制,针对此问题,提出基于扩展有限状态机的高铁信号系统工程测试建模方法和测试用例生成方法.首先,分析高铁信号系统工程测试的特点,提出复杂事件交互和状态同步的测试建模需求,以有限状态机理论为基础,扩展出状态事件和层次性,满足信号系统工程测试中复杂行为关系和状态同步的建模需求,采用Z规格说明语言给出扩展有限状态机的形式化定义,定义扩展有限状态机的格局和同步机制;然后,提出将扩展有限状态机转化为时间自动机的算法,利用时间自动机的测试用例生成算法自动生成高铁信号系统工程测试的测试用例;最后,以高铁信号系统工程测试中的进路控制为例,建立扩展有限状态机模型并生成测试用例,通过变异分析对生成的测试用例进行评估.结果表明:测试用例在检测状态变异和事件表达式变异时的变异评分均为1,具有良好的覆盖度,能够满足高铁信号系统工程测试的需求.

The engineering testing of a high-speed railway signaling system(HSRSS) focuses on the complex behavior relationship and state synchronization among various equipment in the system.Since the testing modeling method for engineering testing lacks complex behavior interaction and synchronization mechanism,the engineering testing modeling method and test case generation method of HSRSS based on an extended finite state machine(EFSM) were proposed.First,the engineering testing characteristics of HSRSS were analyzed,and the testing modeling requirements for complex event interaction and state synchronization were proposed.Based on the theory of finite state machine,the state events and hierarchy were extended to meet the modeling requirements for complex behavior relationships and state synchronization in engineering testing of HSRSS.The formal definition of EFSM was given by using Z specification language.The pattern and synchronization mechanism of EFSM were defined.Then,the algorithm of transforming the EFSM into a timed automata(TA) was put forward,and the test case generation algorithm of TA was used to automatically generate test cases for engineering testing of HSRSS.Finally,with the route control in engineering testing of HSRSS as an example,an EFSM model was established,and test cases were generated.In addition,the generated test cases were evaluated through mutation analysis.The result shows that the test cases have a mutation score of 1 when testing state mutation and signal expression mutation,and they have good coverage,which can meet the requirements of engineering testing of HSRSS.